package ch06;interface ComputerAverage {
	public double average(double a,double b);
}
class A implements ComputerAverage {
	public double average(double a,double b) {
		double aver = 0;
		aver = (a+b)/2;
		return aver;
	}
}
class B implements ComputerAverage {
	public double average(double a,double b) {
		double aver = 0;
		aver = Math.sqrt(a*b);
		return aver;
	}
}
public class Example6_4 {
	public static void main(String args[]) {
		ComputerAverage computer;
		double a = 11.23,b = 22.78;
		computer = new A();
		double result = computer.average(a,b);
		System.out.printf("%5.2f和%5.2f的算数平均值：%5.2f\n",a,b,result);
		computer = new B();
		result = computer.average(a,b);
		System.out.printf("%5.2f和%5.2f的几何平均值：%5.2f\n",a,b,result);
	}
}
		
